Collision sweeping (also known as chaff sweeping) is the practise of reducing the size of a minefield(or clearing it completely) by sending multiple fleets into the field at high speeds. The aim is for them to crash into the field, thus destroying some of the mines and reducing its size. Naturally, it's customary to use cheap ships (thus the moniker chaff sweeping).
A couple of points to note:
- the probability of hitting a minefield is not based on the speed set in the interface, but on the minimum warp speed needed to travel the desired distance moved. eg if you send a ship 60ly at W9 your chances of hitting are the same as travelling at W8.
- ships move according to fleet ID# so make sure your main fleet has a higher ID# than the sweepers.
- as each ship hits the field its size is reduced immediately, so for best effect you should sweep across or to the center of the field.
- Give your sweepers two waypoints, one to sweep the field, and the second to regroup afterward. Otherwise you'll have to give orders to every single fleet to regroup them.(this is especially important with mixed field types)
- Give orders to the sweepers as a single fleet before you split them up.
- Do not send all your sweepers to the same destination as your main fleet, as this can trigger the Target List Overload and Battle Board Overload bugs. Either could result in penalties from the game host for bug abuse, and Battle Board Overload could have direct negative consequences for you as well.
- Can be a good use for out-of-date ships.
- The ships used do not need to be armed. However if they are then any that survive will then sweep the remains of the field "normally" after they move.
Reduction in field for each chaff hit:
- Above 5000 mines, each ship impacting sweeps 1% (tested out to over 140 000 mines).
- From 1000 to 5000 mines, each impact sweeps 50 mines.
- From 200 to 1000, each impact sweeps 5%, rounded down.
- Under 200, each impact sweeps 10 mines.
How many ships do you need?